The Doctor's sonic screwdriver (The Curse of Fatal Death)
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In what some accounts posited as a particular version of reality, (PROSE: The Tomorrow Windows [+]Loading...["The Tomorrow Windows (novel)"], etc.) the "listless-looking" Ninth Doctor carried a sonic screwdriver on his person whilst aboard a Dalek spaceship, which was retained through his successive regenerations into the Tenth, Eleventh, Twelfth and Thirteenth Doctors. Shortly after having regenerated, the Thirteenth Doctor took the screwdriver out, observing as it vibrated that it had three settings. Frustrated, the Doctor's companion Emma grabbed the screwdriver and put it aside. (TV: The Curse of Fatal Death)